Il 06/12/22 10:04, Xiangsheng Hou (侯祥胜) ha scritto:
Hi Angelo,
On Mon, 2022-12-05 at 15:21 +0100, AngeloGioacchino Del Regno wrote:
Il 05/12/22 07:57, Xiangsheng Hou ha scritto:
Add mediatek,rx-latch-latency property which adjust read delay in
the
unit of clock cycle.
Signed-off-by: Xiangsheng Hou <xiangsheng.hou@xxxxxxxxxxxx>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
---
.../devicetree/bindings/spi/mediatek,spi-mtk-snfi.yaml | 7
+++++++
1 file changed, 7 insertions(+)
diff --git a/Documentation/devicetree/bindings/spi/mediatek,spi-
mtk-snfi.yaml b/Documentation/devicetree/bindings/spi/mediatek,spi-
mtk-snfi.yaml
index bab23f1b11fd..6e6ff8d73fcd 100644
--- a/Documentation/devicetree/bindings/spi/mediatek,spi-mtk-
snfi.yaml
+++ b/Documentation/devicetree/bindings/spi/mediatek,spi-mtk-
snfi.yaml
@@ -45,6 +45,13 @@ properties:
description: device-tree node of the accompanying ECC engine.
$ref: /schemas/types.yaml#/definitions/phandle
+ mediatek,rx-latch-latency:
+ description: Rx delay to sample data with this value, the
value
+ unit is clock cycle.
Can't we use nanoseconds or microseconds as a unit here, instead of
clock cycles?
The clock cycle will be various with MediaTek SPI NAND controller which
clock frequency can support 26/52/68/81/104MHz...
It`s may be easy to configure and understand with clock cycle in unit.
Yes, but whatever clock frequency we use, the target is to always wait for
X nanoseconds, right?
Waiting for 5 clock cycles at 104MHz is obviously not the same as waiting
for the same 5 clock cycles at 26MHz: in that case, expressing the value
in nanoseconds or microseconds would make that independent from the
controller's clock frequency as the calculation from `time` to `cycles`
would be performed inside of the driver.
Regards,
Angelo
